Chapter 3 - PSY 0010

• linear perspective


  objects closer together appear father away

  
• texture gradient


  sharper details make objects appear closer

  
• relative size

  smaller object higher in the visual field appear farther away

  
• motion parallax


  when we move, closer objects appear to move faster
• monocular cues (depth perception)


  depth and distance are perceived with one eye

  -motion parallax

  -relative size

  -texture gradient

  -linear perspective
• binocular disparity (depth perception)


  differences in images by left and right eye influence depth perception
• simplicity (Gestalt Laws of Organization)


  patterns are perceived in their most basic manner

  
• similarity (Gestalt Laws of Organization)


  similar look objects are grouped

  
• proximity (Gestalt Laws of Organization)


  elements that are close together are grouped

  
• closure (Gestalt Laws of Organization)


  elements are grouped into closed figures

  
• perception: Gestalt Laws of Organization


  bits of information are organized into meaningful wholes
• gate-control theory of pain


  injury activates receptors that open a gate to pain centers in the brain

  -other signals close the gate and reduce pain:

  ---distracting or competing stimuli (rubbing the wound)

  ---interpretation of the situation
• skin senses

  touch, pressure, temperature, pain

  
  

  -operate through receptor cells at various depths throughout the skin

  -receptors are unevenly distributed throughout the body

  -more receptors in hand and face
• gustation (taste)


  receptor cells on the tongue respond to 5 basic stimulus qualities

  -sweet

  -sour

  -salty

  -bitter

  -umami (savory, meaty) (from food high in amino acids)

  -receptor cells located in taste buds
• olfactory cells


  receptor neurons of the nose

  -humans have over 1,000 different ones

  -each responds to only a few odors
• olfaction (smell)


  occurs when molecules of a substance enter nasal passages
• frequency theory


  entire basilar membrane responds to sound

  -higher pitches = more signals to the brain
• place theory


  different areas of the basilar membrane respond to different pitches

  -front = high pitch sounds

  -back = low pitch sounds
• theories of hearing

  place theoryfrequency theory
• decibels


  measures of the intensity of a sound wave
• amplitude


  height of waves; affects loudness
• pitch

  makes sound seem high or low

  -short wavelength = high pitch
• frequency


  wave cycles per second
• physical aspects of sound


  frequency

  --pitch

  amplitude

  --decibels

  
• basilar membrane (middle ear)


  runs through the cochlea

  -contains hair cells that bend when vibrated and send neural signals to brain

  
• cochlea (middle brain)


  filled with fluid that vibrates in response to sound

  
• 3 bones of middle ear (hammer, anvil, and stirrup) (middle brain)


  amplifies sound from inner ear

  
• eardrum (middle brain)


  vibrates when sound waves hit it

  
• inner ear


  turns vibrations into neural energy
• middle ear


  vibrates in response to sound
• outer ear


  collects sound waves
• sound


  movement of air molecules caused by vibration

  -outer ear

  -middle ear

  -inner ear
• opponent-process theory


  cones are linked in pairs (blue-yellow, red-green, black-white)

  -when one color is stimulated, the other is suppressed

  -ex: blue is stimulated, yellow is suppressed

  -helps explain afterimages
• trichromatic theory (of color vision)


  retina contains three types of cones

  -each responds to specific wavelengths (blue-violet, green, yellow-red)

  -strength of stimulation of each determines color
• feature detectors


  specialized neurons in the visual cortex

  -are activated only by stimuli with specific features

  -ex: specific shapes, patterns, or movement
• processing visual signals

  optic nerve, feature detectors
• optic nerve


  collects signals from the retina

  -sends signals to visual cortex of the brain
• fovea


  the central focal point in the retina, around which the eye's cones cluster
• cones


  cone-shaped cells that are good in bright light

  -concentrated in the fovea (near center of the retina)

  -responsible for sharp focus and color perception
• rods


  cylindrical cells that are highly sensitive to light

  -distributed throughout the retina

  -insensitive to color and focus

  -good for peripheral vision and dim lighting

  -good for night